Nonwoven articles may be formed from a variety of fibrous materials and can vary substantially in form and density. Such materials can be used in a variety of applications, including filtration, battery separation, and sound absorption. High density, porous, nonwoven textiles can be used as a fiber board.
Previously, there were limited ways to improve sound absorption capability of fiber-based acoustic materials. One way to change air flow resistance, and in turn, change sound absorption, is by using short fibers. However, the use of short fibers has been limited because of a lack of ability to effectively process the short fibers, prevent clumping of the fibers due to static electricity, and produce a stable, useful nonwoven web. Prior short fiber processing technologies have been found to produce products that are fragile, easily broken or degraded.
Nonwoven articles, including short fiber-based articles, can be formed into rolls or sheets and can be converted by lamination, coating, molding, stamping, cutting, or can be otherwise fabricated into desired shapes and sizes. In certain applications, nonwoven textiles are molded into three-dimensional shapes for a variety of functional applications.
During the processing and shaping of nonwoven articles, a large amount of waste can be generated. Waste can include the by-products of a process, the portions that are not part of the molded article, the offal, scrapped or flawed parts, the trimmed matrix after die-cutting, and the like. A large proportion of this waste is generated in the form of the trimmed matrix from molded fibrous sheets. It is estimated that about 50% of a sheet that is used to make a molded part goes to waste upon cutting or removing molded parts, thereby creating a material inefficiency.
There is, thus, a need to develop a process that creates a stable, useful nonwoven web from short fibers that can be used to form a nonwoven article. Furthermore, there is a need for a process where the waste can be recycled and used for subsequent parts to reduce waste and costs.